Push-button switch including a sheet provided with a plurality of domed members

• US 5,136,131 A
• Filed: 09/24/1990
• Issued: 08/04/1992
• Est. Priority Date: 05/31/1985
• Status: Expired due to Term

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Komaki, Shigeki
• Primary Examiner(s): Recla, Henry J.
• Assistant Examiner(s): Walczak, David J.
• Application Number:
  US07/587,566
• Time in Patent Office: 680 Days
• Field of Search: 200/5 A, 200/516, 200/512, 200/513
• US Class Current: 200/516
• CPC Class Codes: H01H 13/702 with contacts carried by or formed from layers in a multilayer structure, e.g. membrane switches
• CPC Class Codes: H01H 2209/006 Force isolators
• CPC Class Codes: H01H 2209/014 composed of different layers; Lubricant in between
• CPC Class Codes: H01H 2209/07 metallic
• CPC Class Codes: H01H 2215/006 Only mechanical function
• CPC Class Codes: H01H 2215/022 Asymmetric; Elliptic; Square
• CPC Class Codes: H01H 2215/024 Spider
• CPC Class Codes: H01H 2215/028 alterable
• CPC Class Codes: H01H 2219/011 with integrated photo- or thermovoltaic cell as power supply

Abstract

A switch including a springy metallic sheet having a plurality of integrally formed domed members, and a force removing or absorbing element provided within the sheet. The domed members are provided by pressing at a plurality of predetermined positions of the sheet. The force removing or absorbing element includes first slits provided at the peripheral portions of the domed members and second slits provided within the domed members. The slits are provided for removing or absorbing the force caused by the movements of the domed members and for preventing the influence of force to adjacent key portions, and/or for controlling the operating load upon the top of the domed member.

Claims

1. A push-button matrix switch array comprising:

a flexible and insulative substrate layer having a plurality of first conductive contacts formed on a first major surface of said substrate;

a flexible and insulative key contact layer having a plurality of second contacts formed on a second major surface of said key contact layer;

said key contact layer being formed over said substrate in a parallel and spaced relationship wherein each of said plurality of first conductive contacts are aligned with corresponding ones of said plurality of said second conductive contacts;

a metallic sheet formed on a first major surface of said key contact layer and having a plurality of integrally formed domed members arranged in a two dimensional matrix, each of said plurality of domed members being selectively actuable to enable an electrical connection between corresponding ones of said first and second conductive contacts;

means for uniformly absorbing a radial force which would otherwise be applied to peripheral edges of said plurality of domed members caused by actuation of said plurality of domed members, said means for uniformly absorbing being at least one pair of symmetrically formed apertures around the periphery of each of said plurality of domed members;

means for reducing an operation load applied to each of said plurality of domed members caused by actuation of one of said plurality of domed members, said means for reducing being at least one pair of symmetrically formed apertures through the surface of each of said plurality of domed members, whereby said apertures are positioned such that any radius extending from the center of a domed member to a point beyond said periphery surrounding said domed member will intersect at least one of said apertures; and

means for connecting said metallic sheet to said key contact layer.

2. The push-button matrix switch array according to claim 1, wherein each of said plurality of domed members includes two pairs of symmetrically opposed slits formed therethrough.

3. The push-button matrix switch array according to claim 1, wherein said means for absorbing a radial force comprise a pair of diametrically opposed arcuate apertures formed through said metallic sheet around the periphery of each of said plurality of domed members.

4. The push-button matrix switch array according to claim 3, wherein said means for absorbing a radial force further comprise a pair of diametrically opposed rectangular apertures formed through said metallic sheet around the periphery of each of said plurality of domed members and alternating with said arcuate apertures.

5. The push-button matrix switch array according to claim 4, wherein said means for reducing an operation load comprise four elliptical apertures formed through the surface of each of said plurality of domed members, said elliptical apertures being symmetrically arranged as two opposing pairs of elliptical apertures.

6. The push-button matrix switch array according to claim 5, wherein said elliptical apertures have a longitudinal axis thereof positioned at an angle with respect to said arcuate and rectangular apertures, such that the longitudinal axis of each of said elliptical apertures intersects at least one said one said arcuate apertures and one of said rectangular apertures at a position intermediate an overall length of said arcuate and rectangular apertures.

7. The push-buttom matrix switch array according to claim 6, wherein said angle is at 45 degrees with respect to the intermediate position of said arcuate and rectangular apertures.

8. The push-button matrix switch array according to claim 1, further including means for identifying said plurality of domed members by the use of a decorative film overlying said metallic sheet.

9. The push-button matrix switch array according to claim 8, wherein said decorative film has a shape corresponding to said metallic sheet including a corresponding plurality of integrally formed domed members arranged in a two-dimensional matrix thereby enabling tactile location of each of said plurality of domed members in said metallic sheet.

10. The push-button matrix switch array according to claim 1, wherein said means for connecting said key contact layer to said metallic sheet is by the use of an adhesive.

11. A push-button matrix switch array comprising:

a flexible and insulative substrate layer having a plurality of first conductive contacts formed on a first major surface of said substrate;

a flexible and insulative key contact layer having a plurality of second contacts formed on a second major surface of said key contact layer;

said key contact layer being formed over said substrate in a parallel and spaced relationship wherein each of said plurality of first conductive contacts are aligned with corresponding ones of said second conductive contacts;

a metallic sheet formed on a first major surface of said key contact layer and having a plurality of integrally formed domed members arranged in a two-dimensional matrix, each of said plurality of domed members being selectively actuable to enable an electrical connection between corresponding ones of said first and second conductive contacts;

means for uniformly absorbing force which would otherwise be applied to peripheral edges of said plurality of domed members upon actuation of one of said plurality of domed members, said means for uniformly absorbing including a pair of diametrically opposed arcuate apertures formed through said metallic sheet around the periphery of each of said plurality of domed members and a pair of diametrically opposed rectangular apertures formed through said metallic sheet around the periphery of each said plurality of domed members and alternating with said arcuate apertures;

means for reducing an operation load applied to each of said plurality of domed members upon actuation thereof, said means for reducing including four elliptical apertures formed through the surface of each of said plurality of domed members, said elliptical apertures being symmetrically arranged and having a longitudinal axis thereof positioned at an angle with respect to said arcuate and rectangular apertures, such that the longitudinal axis of each of said elliptical apertures intersects at least one of said arcuate apertures and one of said rectangular apertures at a position intermediate an overall length of said arcuate and rectangular apertures, whereby said apertures are positioned such that any radius extending from the center of a domed member to a point beyond said periphery surrounding said domed member will intersect at least one of said apertures; and

means for connecting said metallic sheet to said key contact layer.

12. The push-button matrix switch array according to claim 11, wherein said angle is at 45 degrees with respect to the intermediate position of said arcuate and rectangular apertures.

13. The push-button matrix switch array according to claim 11, further including means for identifying said plurality of domed member by the use of a decorative film overlying said metallic sheet.

14. The push-button matrix switch array acoording to claim 13, wherein said decorative film overlaying said metallic sheet includes a corresponding plurality of integrally formed domed members arranged in a two-dimensional matrix thereby enabling tactile location of the each of said plurality of domed members in said metallic sheet.

15. The push-button matrix switch array according to claim 11, wherein said means for connecting said key contact layer to said metallic sheet is by the use of an adhesive.